Lexus GS350 ATF Service Advice

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Jan 9, 2010
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Location
Los Gatos, CA
Our GS350 F Sport is nearing 70K; I have been putting off servicing the transmission.
You probably know that a drain only removes about 2.5 quarts; the transmission holds 10 or more I believe...

My plan is to:
Lift and level the car

Drain and measure the fluid
Replace the same plus a little
Run the engine for perhaps 15 to 30 seconds
Repeat the spill and fill process perhaps 3 times

Run engine up to 105* (or whatever spec is)
Open plug to allow straw to set level.

My goal is to drain the pan of new fluid but avoid mixing with old as much as possible.
Question: How long would it take for the transmission pump to empty the pan?
I am guessing 15 to 30 seconds.
Does 3 iterations sound about right?


Of course I will check fluid color each time.
Thanks in advance for your thoughts.

If I change the filter, I will use a factory part.
 
I would suggest going to the Lexus forms and look for a COMPLETE write up for the proper way. I did it with my wife's Rav4 with Redline D6 and added 1.5 Qts of Redline Racing and Low Vis Racing to better natch the viscosity of the D6 and to kill some of the slip agents in the Redline D6. I like a clean shifting trans with some slip, but butter smooth I don't like. 114 deg was the Rav4 #. I installed a 8ft hose from the trans pump exit to the pan and brought it under the drives door. I dumped the pan and added 4 Qts. It pumped into a bucket right there floor by the door by the ignition switch so the minute I saw that the trans pump was sucking air, I killed the car and refilled the pan. I repeated 4 times and used 14 Qt to flush out the garbage WS out for good. it was all burnt at 22,000 miles. I got sick being around the WS it smelled so bad. I had to open the doors in winter and wear a respirator to finish.

You wont have this problem, but I did in Minnesota and others in Canada have had the issue on brand new Rav4 that the trans was slipping with a factory fill because when it is 20 below the fluid constricts to being too low and sucks air. Lucky I was in the car at a 20 below night, I noticed a slip when we left a family party and I told the wife to pull over and idle for 5-8 minutes at 1,500 rpm to warm up and expand the ATF. We made it home fine with no slip and I added another Qt of D6 and I never had an issue again.
 
For something like this I would consider paying for a BG products flush. This way the fluid gets exchanged and you don't have to mess with it.

On my Wife's Scion, I just do a drain plug drop and get a few quarts, that is enough every two years for me.
 
I follow the Lexus GS forum and I know the "proper way". Many say the WS is lifetime fluid. Fooey on that. Or the method I described with only 1 iteration.

I will use the Idemitsu WS equivalent. Full synthetic and great stuff, IMO.

I am not interested in a flush. But thanks for the suggestion.

I am asking to thoughts on my process: how many iterations and how long to move the fluid out of the pan?

Again, thanks to all.
 
I do full transmission flush with AISIN AFW+ synthetic WS compatible oil every 30000 on my FJ Cruiser. I have a Magnefine filter in line with my external Hayden 679 cooler and every flush the oil comes out dark red and my shift quality remains as good as new.
 
I'm tracking with you. Great questions. Are you gonna shift from D to N to R to P as well?

I'd do at least 3 drains. Since you've decided to replace with a different ATF, I'd feel better going 4. You may waste a little money but you would get a higher percentage of new ATF.

Are you gonna use a temp scanning tool or the elaborate "no tool" method to check ATF temp?

Have fun getting that black plastic cover with the two 10mm bolts back in place. Grrrrrr.....

I have no idea about your timing question.
 
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Originally Posted by JustinH
For something like this I would consider paying for a BG products flush. This way the fluid gets exchanged and you don't have to mess with it.

I'm totally for this procedure!!
 
Hmm, I had no issues with WS in my Highlander on original fluid with 145K...did a drain and fill because I don't believe in "lifetime" fluid either but still, performance was good.

Regardless, when I've done multiple drain and fills I've driven for a few minutes in between up to speed...locking up the TC to "mix" the fluid as much as possible before the next drain. Perhaps you can do this on the jack stands in between fills...bring it up to 50mph or so. Getting that little fluid out every time 4 might be the magic number for you.
 
JeffKeryk,

I eventually plan to change the ATF in my GS350 as well, but I have a few years before I reach enough miles. My question for you is on the first item in your list: How do you plan to safely "Lift and level the car"? This is the one thing stopping me from doing the procedure - I do not have access to a lift. All the other vehicles I have changed the ATF on are either 4x4 pickups with enough clearance to crawl under the vehicle, or front wheel drive cars where it is easier to access the transmission.

So, do you have access to a hydraulic lift? How will you lift and level the car?
 
Originally Posted by btanchors
JeffKeryk,

I eventually plan to change the ATF in my GS350 as well, but I have a few years before I reach enough miles. My question for you is on the first item in your list: How do you plan to safely "Lift and level the car"? This is the one thing stopping me from doing the procedure - I do not have access to a lift. All the other vehicles I have changed the ATF on are either 4x4 pickups with enough clearance to crawl under the vehicle, or front wheel drive cars where it is easier to access the transmission.

So, do you have access to a hydraulic lift? How will you lift and level the car?


I have numerous trolley jacks, HF ramps and jackstands.
There is nothing special about the GS; I will simply position the jacks on the frame.
Leveling the car is easy; jackstands in front and floor jacks in back as level height adjusters.

By the way, I would consider doing a trans service early. There is good thought, in my opinion, that the 1st service is the most important because it removes break in materials.
 
If I may add, I put a level on the roof of my car before doing any jacking. That way I know level. Then I do what Jeff says. Jack stands on front at the height I want them and then go to diff and jack there until the level on the roof shows level.

Yeah, I know I have issues.
 
Originally Posted by tbm5690
Hmm, I had no issues with WS in my Highlander on original fluid with 145K...did a drain and fill because I don't believe in "lifetime" fluid either but still, performance was good.

Regardless, when I've done multiple drain and fills I've driven for a few minutes in between up to speed...locking up the TC to "mix" the fluid as much as possible before the next drain. Perhaps you can do this on the jack stands in between fills...bring it up to 50mph or so. Getting that little fluid out every time 4 might be the magic number for you.

I see your point, but I am suggesting something different.
I do not want to mix the fluid. I want to use the transmission to move the new fluid out of the pan replacing it with the old fluid.
Then repeat the spill and fill procedure.

The goal is to drain old fluid and put in fresh.
Hence my question on how long to run the engine to move the new fluid out of the pan with a minimum of mixing old and new.
 
Originally Posted by Gebo
If I may add, I put a level on the roof of my car before doing any jacking. That way I know level. Then I do what Jeff says. Jack stands on front at the height I want them and then go to diff and jack there until the level on the roof shows level.

Yeah, I know I have issues.

Level against the frame might be better than the roof?
 
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I move the magnetic level around on the roof until it shows level on the unjacked car. Then after getting jack stands on front, I just jack the rear end up until the level shows "level" again.

"Magnetic" is key word. I have this 6 inch magnetic level.


How are you gonna check ATF temp?
 
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Originally Posted by Gebo
How are you gonna check ATF temp?

OBD II module and app like Torque. Easy peasey.
OBD II
 
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I know nothing about the product you mentioned. Just make doggone sure it will check ATF temp. A couple of years ago I had one heckuva time finding what would work with my cars.

I had to use a ScanGauge. Cost me like $100
 
Originally Posted by Gebo
I know nothing about the product you mentioned. Just make doggone sure it will check ATF temp. A couple of years ago I had one heckuva time finding what would work with my cars.

I had to use a ScanGauge. Cost me like $100

I linked to the OBD II scanner I bought from Amazon.

I loaded Torque Lite (no AT temp) and ELM Scan for Toyota (displays AT temp).
 
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